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Yeosu weather by month: averages, rainfall & climate trends

Yeosu swings through a wide annual range, with 22.7°C between the monthly means of its warmest and coldest months. The heavier rain months run from April to September. Yeosu weather by month: average temperatures, rainfall, extremes and how the climate has changed since 1940.

Today vs average

−1.8°Chigh below average

17° / 11°Today
19° / 15°Average
see today in detail →

How it's changed

+1.5°Caverage temperature, 2016–2025 vs 1940–1949average temperature vs 1940–4922frost days a year now (2016–2025) · 38 in the 1940sfrost days a year · 38 in the 1940s4days above 30°C a year now (2016–2025) · 0 in the 1940sdays above 30°C · 0 in the 1940s+1.5°C vs the 1940s · see how it's changed →
Weather by montha typical year, averaged over the full recordJanuary, rain 36 mmhigh 6°low 1°February, rain 51 mmhigh 7°low 2°March, rain 90 mmhigh 10°low 6°April, rain 141 mmhigh 14°low 11°May, rain 150 mmhigh 18°low 15°June, rain 223 mmhigh 21°low 19°July, rain 262 mmhigh 25°low 23°August, rain 190 mmhigh 27°low 25°September, rain 167 mmhigh 24°low 21°October, rain 67 mmhigh 20°low 15°November, rain 55 mmhigh 14°low 9°December, rain 30 mmhigh 8°low 3°wettest month July, 262 mm · 1,463 mm a yearsee month by month →

Right now

What it's doing today vs the historical average for this date.
Clear

Right now

11.1°

8°feels like
63%humidity
4°dew point
10 km/hfrom NW
UV index0.0
sunrise06:40sunset17:46day length11h 06m
ThuClear17°11°
FriOvercast21°14°
SatLight rain20°17°
SunOvercast23°19°
MonShowers21°19°
TueClear20°10°
WedClear15°8°

On this date: October 21

Today (forecast)
17° / 11°
Average for October 21
19° / 15°

High below average · −1.8°C

  • Highest since 1940: 21.6° · 2008
  • Lowest since 1940: 9.0° · 1980
  • One year ago: 18° / 16°

Every October 21 in history, coldest to hottest

▲ Daily highs▼ Daily lows

Dots show daily highs (top) and lows (bottom) for each October 21 on record (n = 87). Outlined dots are today's forecast.

Area we sample

Each city's history comes from one ERA5 grid cell, about 28 km across, shown by the dashed box. Near mountains or coasts, conditions can vary across the cell.

Location & data

Historical weather for Yeosu is sampled from the ECMWF ERA5 reanalysis at 34.76°N, 127.66°E, with daily records since 1940.

Coordinates
34.76°N, 127.66°E
Time zone
Asia/Seoul
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

28 of the last 31 days were warmer than the historical average for that date. Average difference: +2.0°C.

Each bar is one day, from morning low to afternoon high. Warm-colored bars are days whose mean ran above average; cool bars ran below. The dot inside the bar is the daily mean. The shaded band is the typical 10–90% range expected for that date. Average = the day's mean temperature averaged across every year of record (1940–2026) for that calendar date.

This date over the years

One dot per year, showing the mean temperature on this calendar date. Dots are warmer or cooler than the long-term average (dashed line); the shaded band is the typical 10–90% range, and the highlighted dot is today's forecast. Based on ERA5 reanalysis: modelled estimates, not station readings.

Weather by month

Average temperatures and rainfall for each month: a typical year, from the full record.

Climate overview

The year peaks in August, at around 27.0°C by mid-afternoon, with nights around 24.8°C. Around 115 nights a year stay above 20°C. The coolest month is January, when afternoons reach about 5.6°C and overnight lows sit around 0.7°C.

Yeosu picks up roughly 1,463 mm a year, with a peak of 262 mm in July and as little as 30 mm in December.

Comparing the record's first decade with its most recent one, Yeosu now averages 1.5°C warmer than it did in the 1940s. Frost days have thinned out, from around 40 a year in the first decade to about 20 now.

Climate graph (climograph)

August is the warmest month, January the coolest: a yearly swing of 23°C. Wettest month: July (~262 mm). Whole year averages ~1,463 mm of rain.

Bars = average monthly rainfall (right axis). Lines = average daily high and low (left axis). Average = each month's value averaged across every year of record (1940–2026).

Rainy days by month

About 83 rainy days a year: most in July (~13), fewest in December (~3).

Bars = average number of days with ≥ 2 mm per month. Hover for the monthly rainfall total.

Monthly wind

Average daily peak wind at 10 m, by month.

Monthly solar energy

Average daily incoming solar energy in megajoules per square metre: the record's own proxy for how sunny the month is.

Yeosu month by month: what to expect

Typical conditions for each month, averaged across the full record (since 1940). Daylight is the time from sunrise to sunset. Highest and Lowest are the most extreme values in the ERA5 dataset (modelled since 1940), so they can differ from official weather-station readings.

MonthAvg highAvg lowRainRainy daysDaylightHighestLowest
January5.6°0.7°36 mm39.9 h15.1° (2020)−9.4° (1967)
February6.8°1.8°51 mm410.7 h15.9° (2009)−8.3° (1977)
March10.3°5.8°90 mm611.7 h16.7° (2023)−4.6° (1977)
April14.3°10.9°141 mm812.9 h20.5° (1999)2.0° (1972)
May18.2°15.5°150 mm813.8 h24.7° (2017)9.6° (1976)
June21.3°19.4°223 mm1014.3 h26.9° (2024)14.0° (1957)
July25.0°23.2°262 mm1314.1 h31.5° (2018)17.2° (1986)
August27.0°24.8°190 mm1113.3 h32.2° (2017)19.7° (1950)
September24.2°21.1°167 mm912.2 h30.4° (2024)13.8° (1956)
October19.5°15.5°67 mm411.1 h26.1° (2024)4.9° (1997)
November13.7°9.2°55 mm410.1 h21.7° (2023)−1.8° (1970)
December8.1°3.4°30 mm39.7 h16.6° (1957)−6.3° (1976)

How it's changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +1.5°C.

Each vertical stripe is one year. Color encodes how much that year's annual mean differed from the long-term average. Average = each year's annual mean compared to the average of all years (1940–2026). cooler ← → warmer

Annual mean temperature

Long-term trend: +0.15°C per decade.

One point per year, showing the temperature averaged across the whole year. The dashed line is the least-squares long-term trend. Based on ERA5 reanalysis: modelled estimates, not station readings.

Seasonal warming

Jun–Aug is warming fastest: +0.17°C per decade.

Each faint line is one three-month period's average per year; the bold dashed line is its long-term trend. Different parts of the year often warm at different rates. Based on ERA5 reanalysis: modelled estimates, not station readings.

Hot days vs frost days

Days ≥ 30°C per year: 0.0 early in the record → 4.2 recently. Frost days: 38 → 22.

Thin lines are raw yearly counts; thick lines are the smoothed trend that removes year-to-year noise. The hot-day threshold is auto-picked per city so the line actually moves. Average = a centered 5-year rolling average to smooth weather noise.

Yearly hot & cold extremes

Hottest day since 1940 in 2017, coldest in 1967: 32.2°C / −9.4°C.

One point per year: the single hottest and coldest day recorded that year.

Annual rainfall

~1,463 mm/year on average. Last decade: +4% vs that average. Long-term trend: +26 mm per decade.

One bar per year of total rainfall. Dashed line is the long-term average. Average = the average annual rainfall across every year of record (1940–2026).

Day-by-day grid

Each tiny square is one calendar day across the full record, about 30,000 days per city. Use the mode switch above the chart: Anomaly colors each day by how far it ran from the historical average for that date (red = warmer, blue = cooler), Daily mean temp shows the absolute mean temperature for the day (useful to see seasons and heatwaves), and Precipitation shows daily rainfall (useful to spot wet/dry seasons and droughts). Average = the long-term average for that calendar date (1940–2026).

Frequently asked questions about Yeosu

Which is the warmest month in Yeosu?
On long-term average, the warmest month in Yeosu is August (mean daily temperature of about 25.9°C) and the coolest is January (about 3.2°C).
How does today's temperature in Yeosu compare to the historical average?
On October 21, 2026, Yeosu is forecast to reach a high of 17.0°C and a low of 11.1°C. The long-term average for this date (the full record since 1940) is a high of 18.8°C and a low of 14.7°C, so today's high is 1.8°C cooler than that average.
How much has Yeosu warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Yeosu is about 1.5°C warmer.
How much does it rain in Yeosu?
Yeosu receives about 1,463 mm of precipitation per year on long-term average, with July typically the wettest month.
What is the average temperature in Yeosu?
Over the full record (since 1940), the annual mean temperature in Yeosu is about 14.5°C. The warmest month is August and the coolest is January.
What are the average temperatures in Yeosu by month?
Average daily highs and lows for each month in Yeosu (°C, full record since 1940): January 6°/1°, February 7°/2°, March 10°/6°, April 14°/11°, May 18°/15°, June 21°/19°, July 25°/23°, August 27°/25°, September 24°/21°, October 20°/15°, November 14°/9°, December 8°/3°.
What is the weather like in Yeosu in summer?
Summer in Yeosu (June to August) is wet and pleasantly warm. June starts at 21°C by day and 19°C at night; by August it is 27°C and 25°C. Rain is steady at around 225 mm a month, spread over roughly 11 days. No season is wetter.
What is the weather like in Yeosu in winter?
In winter, December through February, Yeosu is cold. Afternoons run 6–8°C and nights 1–3°C; January is the coldest month. Rain rises from 30 mm on 3 days in December to 51 mm on 4 days in February. No season is drier.
What is the weather like in Yeosu in spring?
In spring, March through May, Yeosu is wet and cool. March starts at 10°C by day and 6°C at night; by May it is 18°C and 15°C. Rain picks up through the season: 6 rainy days and 90 mm in March, 8 days and 150 mm in May.
What is the weather like in Yeosu in autumn?
In autumn, September through November, Yeosu is mild. September still brings 24°C afternoons and 21°C nights, November only 14°C and 9°C. Rain eases through the season: 9 rainy days and 167 mm in September, 4 days and 55 mm in November.
How many days a year does it rain in Yeosu?
On long-term average, Yeosu has about 83 days a year with at least 2 mm of rain or snow. The annual total is roughly 1,463 mm.

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